Internal-combustion engine



Dec. 2, 1930. H, L, HQRNING I 1,783,714

` INTERNAL coMBUsTIoN ENGINEV Filed Aug. 25, 1928 Patentecl Dec. 2, 1930 UNITED STATES HARRY L. HORNING, OF WAUIiESHA, WISCONSIN', ASSIGNOR. T0 WAUKESHA MOLOB COMPANY, OF WAUKESHA, WISCONSIN, A CORPORATION OF WISCONSIN -INTERNAL-COMBUSIION ENGINE Application filed August 25, 1928.- Serial No. 301,989.

This invention relates to internal combustion engines, and more particularly to their combustion chambers and the immediate appurtenances thereof, to the end of numerous advantages in construction, operation and result.

In the drawings Fig. 1 is a vertical sectional View through an engine head and the upper portion of a cylinder block, constructed `in accordance with my invention, taken substantially in the plane of line 1-1 of Fig. 2;

Fig. 2 is a section taken substantially on line 2-2 of Fig. 1; and ,v

Fig. 3 is a fragmentary vertical sectional View through the head taken through the boss which receives the spark plug, ythe spark plug being shown in `elevation.

Head 1 is secured on the upper end or top of cylinder block 2 in a known manner, a gasket 3 being interposed between the head and the cylinder block. Block 2 is provided with a laterally extending inlet passage 4:`

controlled by an inlet valve 5 which opens upwardly and is operated in a known manner. This passage Opens into a pocket 6 formed in the under face of head 1, the inner portion of which overlies the cylinder and has communication therewith through a throat 7. The under face of head 1 is fiat or planar and overlies the cylinder area and is disposed close to the upper end of cylinder 8 in which the piston 10 reciprocates. The throat 7 overlies one portion of the cylinder area and the flat under face of head 1 overlies the other portion of the cylinder area, and the space between this portion and the piston 10, when in raised position, is slight, as indicated at 11, providing a shielded area or space which occupies a very appreciable portion of the cylinder area.

This is characteristic of a type of engine, in which the fuel charge is initially ignited in a combustion chamber oi'fset from the cylinder, and the piston isvdisposed closely adjacent the overlying portion of the head When in its position of greatest compression, as il- ,ilustrated in Fig. 1. In this type of engine, the successful operation of the engine depends upon its ability to keep the gases `i'nder approaches its position of greatest com'- trapped between the piston and the head comparatively ineffective with regard to detonation. This is accomplished, in the type ofengine referred to, by means of the cooling effect of the large surface volume ratio of this r space when the piston is in its upper position, 5" and by the high velocity'of the gases issuing from this space just before the piston reaches its top position. This space, in the type of engine referred to, is in no sense a combustion chamber, but on the contrary, is so cooled and shielded by the relatively cool walls defining such space as to the fuel chargetrappe in this space, due to high compression vof the charge, as the cyl- 65 pression. The term shielded space? as used herein, may, therefore, be` defined as a space between the piston and the engine head, when the' piston is in its position of greatest 'compression, ysuch space being so related to the Walls dening thesame that the fuel charge trapped in this space is cooled, by contactv with such Walls and by the high velocity of the gases issuing therefrom, to such an extent as to render the fuel charge trapped therein non-effective as to detonation. The term shielded space, used in this sense, is an accepted term inthe art and has a definite signicance. This shielded space is to be distinguished from a space of appreciable vol- I ume, such as would constitute a combustion chamber, since the fuel charge trapped in the latter would inevitably` be of considerable volume and preignition and detonation would occurl'as the piston approached its position of greatest compression, due to the high compression of the fuel chargel in this space. In the engine of my invention, I employ the shielded spacel or area of the type of engine no above discussed, but initially ignite the fuel charge in thisshielded space, 'thus obtaining certain advantages, as will be hereinaftermore fully explained. In this respect, my invention may be considered as an lmprovement over the type of engine which employs an olfset combustion chamber and shielded area and initially ignites the fuel charge in the combustion chamber.

The head 1 is provided with an exhaust 109 prevent preignition of l lintake valve.

described provides a compact turbulent pro-4 passage 12 opening through the side thereof opposite to the inlet passage 4. This exhaust passage is controlled by an exhaust valve 13, the under face of which, when seated, is flush with the under face of head 1. The stem of valve 13 operates through a guide sleeve 14 formed integrally with the head 1, and this valve is operated by a rocker arm 15 in a known manner, it being understood that the valve and rocker arm and associated parts are indicated more or less diagrammatically.

The rocker arm 15 is operated by. a push rod 16 in a known manner.

The engine head 1`and the cylinder block 2 are cored out, where feasible, to permit circulation therethrough of a cooling medium, as is well known in the art. The intake valve 5 may be made large and given a high lift, 1n order to meet demands without increasing engine length or interfering with the complete water jacketing of the valve seat. Since the exhaust valve 13 is removed from the pocket 6, which constitutes the combustion chamber, so that the combustion chamber is free of the hot spot effect of the exhaust valve, the exhaust valve seat may be com'- pletely water-jacketed as in the case of the The structure illustrated and ducing combustion chamber and enables the use of high compression ratios.

When the piston 10 is in its uppermost position, the quantity o f gases or fuel mixture entrapped in the space 11 is negligible, practlcally the ent-ire volume of the charge to be ignited being compressed in the pocket 6. I have found that, by igniting the small charge or volume of fuel mixture in the shielded space 11, a more uniformvflame propagation is obtained than is possible where the charge 1s ignited in the pocket or combustion chamber 6, and smoother operation results. I accomplish this by mounting a spark plug 17 1n a suitable boss 18 provided in head 1, this llapss opening, at its lower end, into the space The sparkplug is of such length that the electrodes'thereof are disposed within the lower portion of boss 18 in a space or ignition chamber 19 defined by the lower portion of the boss. By means of the spark plug, the charge is ignited in the shielded space 11, lnitially, and this serves to ignite the main charge in the pocket or combustion chamber 6. By thus igniting the fuel charge initially at the portion thereof where detonation is most apt to occur, I forestall, and thus prevent, any tendency to detonate. In this manner I provide, in conjunction with the other features of my invention illustrated and above described, an engine of simple construction and high eiiiciency in which any tendency toward detonation is counteracted.

` What I claim is 1. In an internal combustion engine, a cylinder, a piston reciprocating in the cylinder, said engine having an intake passage lying alongside the cylinder, a head having a pocket overlying said intake and part of said cylinder and having a portion overlying and close to the remainder of the cylinder area, said overlying portion of the head forming with the piston, when in its raised position, a shielded space, the head having an exhaust passage opening through the overlying portion thereof, valves forsaid passages, and means for igniting the charge in said shielded space.

2. In an internal combustion engine, a cylinder, a piston reciprocating in the cylinder, a head having a pocket overlying a portion of the cylinder area, said head having a portion overlying and close to the remainder of the cylinder area, the engine having an inlet passage opening into the pocket andan exhaust passage opening into the cylinder, valves for said passages, said overlying portion of the head forming with the piston, when in its raised position, a shielded space, and means for initially igniting the charge in said shielded space.

3. In an internal combustion engine, a cylinder, a piston reciprocating in the cylinder, said engine having an intake passage lying alongside said cylinder, a head having a pocket overlying said intake and a part of said cylinder and also having a portion overlying and close to the remainder of the cylinder area, said pocket representing substantially all of the eective combustion space when the piston is in the position of greatest compression and said piston and the overlying portion of the head forming a .shielded space when the piston is in said position, the head having an exhaust passage opening through said overlying' portion thereof, valves for said passages, and means for igniting the charge in said shielded space.

4.. In an internal combustion engine, a cylinder, a piston reciprocating in the cylinder, a head having a combustion chamber communicating with the cylinder and also having a portion overlying and close to thecylinder area, said engine having an inlet passage opening into said chamber and an exhaust p.ssage opening into 4the cylinder, valves controlling said passages, said overlying portion of the head forming with the piston, when in its position of greatest compression, a shielded space, and means for initially igniting the charge in said space.

5. In an internal combustion engine, a cylinder, a 4piston reciprocating in the cylinder, a combustion chamber adjoining and cornmunicating with the end of said cylinder, a wall overlying and close to the cylinder area and forming with the piston, when in its position of greatest compression, a shielded space, the combustion chamber representing substantially all of the effective combustion space when the piston is in said position, said engine having an inlet passage opening into said chamber and an exhaust passage opening into the cylinder, valves controlling said pas'- sages, and means for-initially igniting thel charge in said space. l 6. In an, internal combustion engine, a

cylinder, a piston reciprocating in the cylinder, said engine having a combustion cham-4 ber adjoining and communicating with the end of' said cylinder, a wall overlying and close to the cylinder area and forming with the piston, when in its position of greatest compression, a shielded space, the combusuVtion chamber representing substantially al1 of the effective combustion space when the piston is in said position, the engine having an inletl passage opening into said chamber, and an exhaust passage opening into the cylinder, valves controlling said passages, said Wall, having an ignition lchamber openingv into the shielded space, said ignition chamber being minute relative to the combustion chamber, -and means for initially igniting the charge in the ignition chamber.;-

.7. In an internal combustion enginea cylinder, a piston reciprocating in the cylinder,

a head having a combustion chamber communicating with the cylinder and also having a portion overlying and close to the cylinder area, said englne having an (inlet passage y opening into-said chamber and an.1 exhaust passage opening into the cylinder, valves controlling said passages, said overlying portion of the head forming with the piston,

' When* in itsl position of greatest compression,

a shielded space, and spark means for igniting the charge in said space.

In witness'vvhereof, I hereunto subscribe o my name this 20th day of August, 1928.

HARRY L. HORNNG. 

